This invention relates to an image signal conversion system, and is suitably applied to formation of pictorial image, which has been shot by a video camera, for example, on a movie film.
There is a conventional electronic beam recorder (EBR) as an image signal conversion system which forms an image, which has been shot by a video camera, on a movie film.
More specifically, in an image signal conversion 1 (shown in FIG. 1) having an electronic beam recorder (EBR), video image signals VD1 which have been received from a video camera 2 are temporarily recorded in a recording video tape recorder (VTR) 3. Then, the signals are low speed reproduced by a low speed reproduction VTR 4 to be inputted to an EBR device 5.
In the EBR device 5, video image signals VD2 which are low speed reproduction image signals are inputted to an image signal conversion circuit unit 6 where the signals undergo a predetermined signal processing to produce film record signals VD3, which are inputted to a beam gun 8 of an EBR unit 15 following. The film record signals VD3 are produced by sequentially and intermittently outputting each of red, green and blue components of one frame of image data.
An electronic beam BM is scanned by beam gun 8 over a black and white film 9, and is modified in intensity by the film record signals VD3 inputted, so that a color picture is formed only in contrast on the black and white film 9 by film record signals VD3.
In the pictures formed on the black and white film 9, each frame is assigned to every one of red, green and blue components of a frame of picture which have been intermittently outputted from the image signal conversion circuit unit 6 as shown in FIG. 2.
More specifically, in the EBR unit 15 a red component contrast image FR1 is formed by recording a red component contract of film record signals VD3 in a first record region of the black and white film 9, and thereafter the black and white film 9 is fed one frame and is then stopped. Then, a green component contrast image FG1 is formed by recording a green component contract of film record signals VD3 in the second record region, and thereafter the black and white film 9 is further fed one frame and is then stopped. Then, a blue component contrast image FB1 is formed by recording a blue component contract of film record signals VD3 in the subsequent third record region.
In contrast images FR1, FG1 and FB1 of respective red, green and blue components of each of reproduced images which have been outputted from the low speed reproduction VTR 4 are then sequentially formed on the black and white film 9 in the described order.
Contrast images FR1, FG1 and FB1 of respective primary colors formed on the black and white film 9, the red component contrast image FR1 is recorded in a first recording region on a color negative film 11 through a red filter R of a filter 10, the green component contrast image FG1 is recorded in the first recording region on the color negative film 11 through a green filter G of the filter 10, and the blue component contrast image FB1 is recorded in the first recording region on the color negative film 11 through a blue filter B of the filter 10. Thus, a color negative image FCOLN which is formed by superposing the red, the green and the blue components is formed in the first record region of the color negative film 11.
The images of the color negative film 11 are printed to a color positive film 12, which is thereby used as a movie film.
In the image signal conversion system 1 having the electronic beam recorder, image signals are outputted from the low speed reproduction VTR 4 at a 1/30 low speed of the ordinary image transmission speed, and in the image signal conversion circuit unit 6 and the EBR unit 15, operations of the signal processing system are preset to the transmission speed of the image signals.
Accordingly, in the image signal conversion circuit unit 6 and the EBR unit 15 operations proceed on the basis of the time preset, and there is therefore a problem in that image oscillation is generated in images formed on the film since a small variation in speed of image signals outputted from the low speed reproduction VTR 4 causes both signal processing operation of the image signal conversion circuit unit 6 and speed of inputted image signals to be shifted.
As one method to solve this problem, there is considered a method to make the low speed reproduction quality of the low speed reproduction VTR 4 improve highly accurate by redesigning the low speed reproduction VTR 4.
An attempt to make redesign all of the low speed reproduction VTR used in the image signal conversion system 1 to redesign makes it less easy to fabricate the image signal conversion system 1, and hence such a solution is still insufficient.